Boston will try to avoid a third straight loss Friday night when the Mavericks welcome back forward Shawn Marion and Celtics guard Jason Terry, who makes his return to Dallas after a long and successful run with the team.
Up by as many 13 points in the third quarter Wednesday, the Celtics (36-31) lost 87-86 at lowly New Orleans on a last-second tip-in by No. 1 overall pick Anthony Davis.
The meltdown didn't come as a major surprise to coach Doc Rivers.
"We started dancing around, stopped defending (starting late in the second quarter). You could see our guys laughing and joking," he said. "We don't learn because we have done this three or four times this year."
With 15 games left, the Celtics can't afford for this to continue if they're going to have any chance at a top-four spot in the East and home-court advantage in the first round of the playoffs.
Boston is 3 1/2 games behind fourth-place Brooklyn and 1 1/2 back of fifth-place Atlanta. The Nets won 113-96 over Dallas (32-36) on Wednesday while the Hawks defeated Milwaukee 98-90.
The Celtics are also in contention for a sixth consecutive Atlantic Division title as they sit 4 1/2 games behind New York.
While Boston looks to improve its 2-10 road record against the West, the Mavericks are trying to get back into the win column after opening a season-high six-game homestand Wednesday.
Advancing to the postseason for a 13th consecutive season is in doubt as Dallas trails the eighth-place Los Angeles Lakers by 3 1/2 games.
The Mavericks, though, could get a boost -- especially defensively and on the boards -- with Marion, the team leader with 7.9 rebounds per game, expected to play after missing eight games with a strained left calf. Dallas went 5-3 with Marion sidelined and was outrebounded by an average of 12.3 in the losses.
"We definitely could have used some of his defense the last couple of games," forward Dirk Nowitzki told the Mavericks' official website. "Our defense has been terrible (giving up 107 or more in each of the last three games) and he's our best defender on the perimeter. .... So it's definitely going to be good to see him back."
The Mavericks also expect Terry to get a warm welcome after he signed with Boston in the offseason after spending eight years with Dallas, including its title run in 2010-11.
"Well, he'll get a great reception," coach Rick Carlisle said. "He's one of the most beloved players I think in the history of this franchise because of his personality, his relationship with the fans and the community and he was a great player."
Terry had 10 points the first time he faced his former teammates, a 117-115 double-overtime win Dec. 12. Paul Pierce scored 34 to help Boston snap a four-game skid in this series.
Nowitzki will face the Celtics for the first time in 2012-13 after missing the previous game with a knee injury. His 26.9 scoring average in 26 games versus Boston is his highest against any team.